Show notifications settings per account

from a user request:

currently, the “show notifications” setting applies to all accounts.
There are situations where you want to change this setting per account instead, especially after the multi-account notifications feature was introduced.

maybe do not add additional switches, but just treat the existing ones as per-account. this is also true for most other settings, so, it also makes sense from that point of view.

see for some previous discussions

I think the main problem is muting other accounts, so while it can be nice to change notification settings per account, for example giving each account their own notification sound (in the future), I think the mute state might be better also shown in the account switcher?

probably makes sense, we can do this similar to what we’re doing for muted chats